Process of preserving hydrogen peroxid solution.



MAX SCHLAUGK, OF HANOVER, GERMANY.

PRGOESS OF PRESERVKNG HYDROGEN PEROXID SOLUTION.

No Drawing.

Specification. of Letters Patent.

Patented May it}, it Slit.

To a-ZZ whom it m 07 concern:

Be it known that 1, MAX Sclinujoii, iSld ing at; Hanover, in the Kii'igdom of Prussia and the German Empire, have invented certain new and usetnl improvements in Procsses for the Preservation of Atpieous ll drogen Peroxid Solutions, of which the toilowing a spetatication. I

it is well known that aqueous solutions of hydrogen peroxid decompose very quickly. In order to prevent such decomposition it has been suggested that acids like sulfuric acid, hydrochloric. acid. phosphoric acid, acetic acid, oxalic acid and others be adde to the solution. The addition of such acids does not, however, result in a complete pres ervation of the solutions. 'Whcnercr the hydrogen peroxid molecule commences to split up, the decomposition proceeds very rapidly so that the solution alter a few recks contains merely traces of hydrog n peroXid. Apart from that, the addition or acids prevents or intcrteres with thcgcneral application of such hydrogen peroxid solutions. With a view to avoiding that disadvantage small quantities of acylamuls or aeylimids or uric acid have been added to the aqueous solutions of hydrogen pcroxid. No doubt, some beneficial ctl'cct was thus a ttaiucd, inasmuch as the hydrogen pcroxid could be kept undccomposcd tor a greater length of time, but the success was not cornplete. I have now found that hydrogen pcroxid solutions may be preserved undecomposed for a greater length ot time than heretofore by the addition of small quanti= tics of paraiicctylainidophcnol and the addition of that substance to the solution terms the object of the present; application.

The addition of paraiicetylamidophcnol has the great advantz'ige that not only the hydrogen pcroxid can be kept unlh-ctimposed l 1 l l l l acid and experiments have Application filed Janu' ry 12. 191i. Serial No. 602.134.

for a longer time but its disinfecting property is also increased whereby such solutions become specially suitable in dentistry and for cosmetic purpos s. It has also been {no posed to employ eicoi-iogcn for the preservation of hydrogen pcroxid. 'lhe ciconogcn the sodium salt of an amidonaphtholsul tonic shown that in its ctt'ect itcomes next to the paraiicctylan1idophcnol. However, the latter has the advantage compared with the ciconogen that it does not discolor the hydrogen pcroxid solullolr. whereas the ciconogen produces such discoloration.

(,omparative experiments specially made with some of the best known means for the preservation of hydrogen pcroxid solutions have proved beyond doubt the increased cllii-icncy oi the paraiicctyl:nnidophcnol.

As a rule an addition of 1 gr. of paraEicetyL amidophenol to 1 liter of 10 vol. {14) hydro gen pcroxid solution is quite sullicient to keep the solution practically undccomposcd for about sixmonths.

\Vhat I claim is:-

l. A process for the preservation of aqueous solutions of hydrogen pcroxid consisting in adding to those solutions a small quantity of paraiicctylamidophcnol.

2. Thohcrein described process for the preservation of aqueous solutions of hydrogen peroxid which consists in adding apn'oxim'atcly one gram of paraiicetylan'iido-' phenol to one liter of approximately 10% volume hydrogen peroxid solution.

In testimony whereof I altix my signature in presence of two witnesses.

MAX SCIILAUGK. 

